Information from FAO Species Identification Guide Western Central Atlantic
Rock crab - Cancer irroratus
Diagnostic characters: Carapace approximately 2/3 as long as wide, convex, granulated; front with 3 teeth, middle one exceeding others and depressed (flattened dorsoventrally); anterolateteral margins (excluding inner orbital angles) divided into 9 lobes or teeth with edges granulate; notches between teeth continued on carapace as short, closed fissures giving teeth a pentagonal character. Pincers moderate-sized, shorter than second legs, ridges granulated, carpus with sharp inner dorsal spine. Colour: yellowish, closely dotted with dark purplish brown, becoming reddish brown after death.
Size: Maximum width: male 135 mm; female 113 mm.
Habitat, biology,and fisheries: This is basically a cold-water species centred in the region north of Area 31. It
ranges in depth from the low-water mark to 575 m. Small to medium-sized crabs move into shallower depths, especially in winter, whereas larger ones occur in deeper water. Feeds mainly on molluscs, echinoderms, and other invertebrates. Mainly outer continental shelf and beyond, often caught along with lobsters. Caught with bottom trawls and lobster traps. Marketed fresh. Separate statistics for this species are collected only for Area 21 (catches from 1984 to 1998 totaled 10 744 t).
Distribution: From Labrador to off Miami, Florida. Southward (Carolinas) only in deep water.